The present invention relates to a material comprising a benefit agent and a deposition aid for deposition of the benefit agent onto a substrate. It further relates to a method of depositing a benefit agent from a dispersion onto a substrate.
Conventionally the deposition of the benefit agent from a treatment composition depends upon the attractive forces between the oppositely charged substrate and the benefit agent. Such adverse charge considerations can place severe limitations upon the inclusion of benefit agents in compositions where an active component thereof is of an opposite charge to that of the benefit agent. For example, cotton is negatively charged and thus requires a positively charged benefit agent in order for the benefit agent to be substantive to the cotton, i.e. to have an affinity for the cotton so as to absorb onto it. Often the substantivity of the benefit agent is reduced and/or the deposition rate of the material is reduced because of the presence of incompatible charged species in the compositions.
Alternatively, when deposition of a conventional benefit agent is effected by mechanisms that do not rely upon charge interaction but upon other non-covalent forces, for example soil release polymers, other problems may occur, namely where interaction of an anionic surfactant with the benefit agent can also make the material so negatively charged and/or soluble as to overcome the other attractive interactions.
Furthermore, there is frequently another complication in achieving optimum deposition of a benefit agent onto a substrate, in that, the need for solubility of the benefit agent in the medium used to treat the substrate is in principle, incompatible with the requirement for the benefit agent to deposit/adsorb onto the substrate.
WO 00/18861 describes a water soluble or water dispersable polysaccharide based rebuild agent for deposition onto fabric during a treatment process wherein a benefit agent is attached to the rebuild agent. However the significance of the particle size for deposition has not been recognised by this document
The present invention is directed towards materials for solving one or more of the above problems.
Accordingly, a first aspect of the present invention provides water-dispersible particle wherein the material comprises:
i) one or more polymeric materials having an average repeat unit (I): 
xe2x80x83wherein at least one or more R groups of the polymer are independently selected from H, a hydrolysable group or a linker group in which when R is a hydrolysable group the degree of substitution is 0 to 3 and when R is a linker group the degree of substitution is 0.01 to 3;
(ii) a benefit agent attached to the deposition enhancing part;
xe2x80x83characterised in that the particle has a particle size from 20 to 5,000 nm
By water-dispersible, as used herein, what is meant is that the material forms a finely divided suspension on addition to water or another aqueous solution
A second aspect of the present invention also provides a method of depositing a benefit agent onto a substrate by applying said material to the substrate.
A third aspect of the present invention also provides compositions comprising a material according to the first aspect of the present invention.